Hydroplane



HYDROPLANE Filed June 16 momma Patented Dec. 29, 1925.

UNITED STATES GUNNAR J'. IARTVIG, OF EIGHLAD PARK, MICHIGAN.

HYDROPLANE.

Application filed June 16, 1924. Serial No. 720,156.

To all whom it may concern:

Be it known that I, GUNNAR J. HARTVIG, a subject of the King of Great Britain, residing at Highland Park, in the county of Vifayne and State of Michigan, have invent ed certain new and useful Improvements in l-lydroplanes, of which the following 'is a specification, reference being had therein to the accompanying drawings.

This invention relates to hydroplane boats wherein the hull is intended at high speeds to rise in the water and so reduce resistance to the forward motion of the boat; and has for its object to still further assist in the raising of the hull at such high speeds to better accomplish the desired friction reduction.

ln the common designs of hydroplane the effect of rapid motion has been to raise the bow of the boat resulting, however, in increase in the draft of the stern of the boat even though the surface of the hull presented to the water has been decreased, and this depression of the stern is very undesirable and it will be obvious that, if avoided, a greater speed of the boat may be attained. Accordingly, it is the purpose of this invention to provide for the elevation of the hull of a hydroplane when traveling at high speed whilst more nearly maintaining the said hull in horizontal position, and further objects subsidiary to or resulting from the aforesaid objects, or from the construction or operation of the invention as it may be carried into effect, will become apparent as the said invention is hereinafter disclosed.

ln carrying the said invention into effect, l may provide in combination with the hull of a vessel a series of transversely disposed planes arranged beneath the said hull and in spaced relation to one another and to the bottom of the hull, being preferably supported by struts having a streamline cross sectional configuration offering minimum resist-ance to an opposed body of water, certain of said planes being arranged abaft the propeller of the boat and above the axis thereof whereby these latter planes will effect the elevation of the stern of the hull when the said hull is traveling at a speed sufficient to effect the reduction of this draft due to the action of the forward planes; and I prefer to arrange a rudder -abaft the stern planes and extending therebelow to admit of directional control of the hydroplane when so raised by the planes referred to. All of which is more particularly described and ascertained hereinafter, by way of example, having reference to the accompanying drawing, wherein Figure l is an elevation of the hull of a vessel embodying the said invention;

Figure 2 is a stern View of the same, and

Figure 3 is a transverse section taken on the line 3"-3* of Figure l.

Similar characters of reference indicate similar parts in the several figures of the drawing.

1 indicates the hull of a vessel provided with a propeller 2 mounted upon a propeller shaft 3 driven by the engine fl, the said hull being provided with forward planes 5 intermediate planes (i and stern planes 7 which are supported and spaced from the bottom of the said hull by struts 8 at the front and baclr thereof, these struts being preferably of streamline configuration in cross section in order to reduce the resistance to the niotion of the boat.

The said planes are more or less inclined upwardly toward their front edges in order that they may eect a lifting of the hull when the same is driven through the water at a high speed to reduce the surface of the hull presented to the water at such speeds. And it will be obvious that the stern planes 7 will materially assist in elevating the stern of the vessel at such times thereby reducing the tendency of the stern to be depressed into the water and cause an undesirable drag therein.

In order to render the action of the stern planes T more positive it is preferred that the propeller 2 be arranged with its axis below the said stern planes as illustrated in the drawing, so that when the said stern planes are in action the propeller 'will remain immersed and thereby be permitted to properly function, whilst at the saine time the stream from the propeller will be directed against the underside of the said plane 7 and assist in its elevation operation. The rudder 9 is shown as also extending substantially below the planes 7 whereby it may perform its directional control of the vessel when the hull is so elevated by the said plane.

This invention may be developed within the scope of the following claims without departing from the essential features of the said invention and it is desired that the specification and drawing be read as being Cil merely illustrative and not in a limiting sense except as necessitated by the prior art.

What I claim is l. In combination with the hull and propeller of a vessel, hydro-planes spaced below said hull forward of said propeller, and stern planes spaced below said hull abaft said propeller7 said planes being supported by struts at the front and back thereof.

2. In combination with the hull and propeller of a vessel7 hydro-planes spaced below said hull forward of said propeller, and stern planes spaced below said hull abaft and substantially above the a-Xis of said propeller, said planes being supported by 15 struts at the front and back thereof.

3. In combinationl with the hull and propeller of a vessel, hydro-planes below said hull forward of said propeller and stern planes spaced below said hull abaft and 20 substantially above the axis of said propeller, and a rudder' to the rear of and of greater draft than said stern planes.

In testimony whereof I aiix my signa-ture.

` GNNAR J. Hirnfrvre. Y 

